I have the laboratory key, but where is the laboratory?
Found three jumpswiches and need one more.
At the beginning on the right side, after the slopes high up and after the swich in the opened wooden box.

I used the code on the keypad after using the fertilizer after completing the laboratory which moved the pedestal near the chained technoegyptian. However nothing happens if I use CTRL on that pedestal. I have been everywhere and can find nothing else to do and no more objects to pick up. I still have 4 flamers left that are unused. What is missed, if anything?

The only place I haven't been is the space-time pathway with the monkey swing/climbable surfaces to the exit portal to leave the level because I can't find a place to use the rockets to get on it. I'm assuming this will become available after the pedestal is activated or such.

Perhaps this is bug....since I did encounter a fatal bug after the laboratory which rendered the ESC key completely useless and I had to use CTRL-ALT-DEL to kill the program and restart the computer since HyperSquare crashes corrupt the desktop. The game will crash after 6 savegame reloads from deathtrap actions that are unsuccessful (e.g. rocket use, difficult jumps, etc.). Using an earlier save before leaving the laboratory to the blue ice water area prevented the ESC key bug.

Thanks Vimmers. I just found it. I never even noticed that upper incline (hard to spot unless you look up at the sky) since the crane seemed to be only a way to get to the code area. That critical item was harder to find than most secrets. And the secret in this level was practically spoonfed to Lara Croft as it was so easy to find.

If the boxer thumper wasn't there, then the missing item would have been easier to notice.

However, I could not find anything to do or pick up in the garbage dump sublevel of "Demon in Chains" at the end. The sole purpose seemed to be to make a tricky rockets move to exit the level and also stare at the robot technoegyptian (?) that was trying to get unstuck in the middle of the area.

Did I miss something in the garbage dump or was it merely a remnant of an uncompleted level and a programmatic placeholder?

it was intended for the boos battle, but if he got stuck...
anyhow it was not an uncompleted level, it was only for the sake of the representation of Nairobi. Nairobi is a city that has very rich areas with great skyscrapers, the most famous were represented in those 3 levels, but has even problems with poverty and distribution of the resouces, people live in those wooden ruined houses you saw in that sublevel and live without a job or with very, very low income. If you search for Nairobi
pictures on internet, you can see bidonvilles next to rich areas and you can't believe it's the same city... I represented Nairobi's art, fashion, richness, architectures, I couldn't skip this other aspect, before leaving that area for a new location